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241.
美国现有的版权法律条文不能有效地应对数字出版商们的忧虑.尽管数字作品可以享受和印刷作品同等的版权保护,我们似乎仍然需要新的法律条文和理论来应对数字作品和技术的特殊性质.在面对与数字侵权有关的问题上,美国通过立法、改进美国版权署的职能以及签订国际条约或协定,缓慢开始颁布一些关于数字侵权的条文.数字侵权虽然在庭审中得以应对,但法庭运用的是传统版权概念中的"合理使用"来分析数字侵权.目前,人们只能通过诉讼的方式迫使美国法庭建立一套能充分解决电子侵权的法律体系.  相似文献   
242.
This study used semistructured interviews and grounded theory to look for characteristics among college undergraduates that predicted persistence into Ph.D. and M.D./Ph.D. training. Participants in the summer undergraduate and postbaccalaureate research programs at the Mayo Clinic College of Medicine were interviewed at the start, near the end, and 8–12 months after their research experience. Of more than 200 themes considered, five characteristics predicted those students who went on to Ph.D. and M.D./Ph.D. training or to M.D. training intending to do research: 1) Curiosity to discover the unknown, 2) Enjoyment of problem solving, 3) A high level of independence, 4) The desire to help others indirectly through research, and 5) A flexible, minimally structured approach to the future. Web-based surveys with different students confirmed the high frequency of curiosity and/or problem solving as the primary reason students planned research careers. No evidence was found for differences among men, women, and minority and nonminority students. Although these results seem logical compared with successful scientists, their constancy, predictive capabilities, and sharp contrast to students who chose clinical medicine were striking. These results provide important insights into selection and motivation of potential biomedical scientists and the early experiences that will motivate them toward research careers.  相似文献   
243.
Theory-of-mind (ToM) abilities were studied in 176 deaf children aged 3 years 11 months to 8 years 3 months who use either American Sign Language (ASL) or oral English, with hearing parents or deaf parents. A battery of tasks tapping understanding of false belief and knowledge state and language skills, ASL or English, was given to each child. There was a significant delay on ToM tasks in deaf children of hearing parents, who typically demonstrate language delays, regardless of whether they used spoken English or ASL. In contrast, deaf children from deaf families performed identically to same-aged hearing controls (N=42). Both vocabulary and understanding syntactic complements were significant independent predictors of success on verbal and low-verbal ToM tasks.  相似文献   
244.
The use of function words in 135 essays written by deaf college underclassmen in developmental and credit-bearing English composition classes is described and compared with Standard English (SE) versions of teh same essay. If student and SE version were the same, this was considered mastery; if the student omitted a word, this was considered avoidance; and if the student added a word, this was considered overuse. The deaf students varied from SE more for function than for content words. They demonstrated low mastery of independent clause markers, demonstratives, third-person singular neuter pronouns, and modals related to possibility, but had relatively high mastery of the first-person singular; and some punctuation. These students strongly avoided some dependent clause markers, some demonstratives, the indefinite article, punctuation except for periods and commas, and the modal verbs may, might and should , but greatly overused other dependent clause markers, the second person and third-person pronouns, quantifiers, the verb do, and the modals could and will. They were also more likely to produce run-ons than fragments.  相似文献   
245.
This article examines how 31 triads of 6- to 10-year-old children from 3 cultural backgrounds organized their interactions while folding Origami figures. Triads of children whose families had immigrated to the United States from indigenous heritage regions of México (and whose mothers averaged only 7 grades of schooling) coordinated more often as an ensemble, whereas triads of European heritage U.S. children whose mothers had extensive schooling more often engaged dyadically or individually. When the European heritage children did engage as an ensemble, this often involved chatting rather than nonverbal conversation regarding folding, which was more common among the Mexican heritage children. Mexican heritage U.S. triads whose mothers had extensive schooling showed an intermediate pattern or resembled the European heritage children.  相似文献   
246.
Why are hyperactivity and academic achievement related?   总被引:1,自引:0,他引:1  
Although a negative association between hyperactivity and academic achievement is well documented, little is known about the genetic and/or environmental mechanisms responsible for the association. The present study explored links between parent and teacher ratings of hyperactive behavior problems and teacher-assessed achievement in a sample of 1,876 twin pairs (mean age 7.04 years). The results did not differ across rater, nor were there significant differences between males or females or for twins in the same or different classrooms. Hyperactivity was significantly correlated with achievement. Multivariate model-fitting analyses revealed significant genetic and nonshared environmental covariance between the two phenotypes. In addition, bivariate heritabilities were substantial, indicating that the phenotypic correlations between hyperactivity and achievement were largely mediated by genetic influences.  相似文献   
247.
The aims of this study were (a) to determine whether Spanish children with reading disabilities (RD) show a speech perception deficit and (b) to explore the locus and nature of this perceptive deficit. A group of 29 children with RD, 41 chronological age-matched controls, and 27 reading ability-matched younger controls were tested on tasks of speech perception. The effect of linguistic unit (word vs. syllable) and type of phonetic contrast (voicing, place and manner of articulation) were analyzed in terms of the number of errors and the response time. The results revealed a speech perception deficit in Spanish children with RD that was independent of the type of phonetic contrast and of linguistic unit.  相似文献   
248.
Phonological awareness, phonological memory, and phonological access to lexical storage play important roles in acquiring literacy. We examined the convergent, discriminant, and predictive validity of these phonological processing abilities (PPA) in 389 3-, 4-, and 5-year-old children. Confirmatory factor analysis supported the validity of each PPA as separate from general cognitive ability and separate from each other. Multigroup structural equation modeling (SEM) with mean structure demonstrated that older preschoolers have better developed latent PPA than younger preschoolers but that the structure of PPA is equivalent. RAN was found uniquely associated with letter knowledge and text discrimination in younger preschoolers, and PA was found uniquely associated with word reading skills in older preschoolers. Finally, general cognitive ability was only indirectly associated with emergent literacy via PPA. These results highlight the importance of PPA in the early literacy development of English-speaking preschool children.  相似文献   
249.
本文以维吾尔谚语中有关女性的丰富多彩的谚语为依据,分析维吾尔族对女性带有时而赞美、时而贬损色彩的矛盾的看法,说明历史上人们对女性的看法和评价,指出这种矛盾的看法存在于生活的方方面面,渗透到社会家庭生活的深层。  相似文献   
250.
论析小说     
小说是文学的一种题裁,即文学分小说和诗歌两类。小说也称散文体作品、非韵文体作品。小说的主要描写方法是散文体形式描写方法或非韵文体描写方法。小说也分抒情和叙事两种。从古至今,小说像诗歌一样遵守一定的规律而发展,以后的发展也必须遵守严格的规律和标准。  相似文献   
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